As a kind of new illuminate light source with an outstanding advantage of its energy saving, environmental protection, high shining efficiency, and long life, an LED is widely used in various situations. Presently, a high power LED light source as a lamp could be used as a street lamp, a wall washer lamp and a large lamp. However, a high power LED will produce a lot of heat, which if not dissipated immediately, will damage the LED by high temperature and affect the using life. Therefore, good heat dissipation is needed. FIG. 1 is an existing lamp comprising a heat dissipation substrate 1 with heat dissipation patches 10 on it. Existing lamps normally use heat dissipation patches to dissipate heat, but as the interspaces of the heat dissipation patches array are in parallel if air flows vertically to the heat dissipation patches, the ventilation will not be smooth in the interspaces of the heat dissipation patches, namely the outside air will not make a good effect to the heat dissipation of the lamp.